Machine for facing millstones



(No Model.) 2 Sheets-Sheel: 1.

J. T. OBENOHAIN. MACHINE FOR FACING MILLSTONES.

No. 282,761. Patented Aug. 7,1883.

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J. T. OBENOHAIN. 1

MACHINE FOR FACING MILLVSTONES. No. 282,761. Patented Aug. 7,1883.

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MACHINE FOR FACING MILLSTONES.

SPECIFICATION forming part of LettersPatent No. 282,761, dated August '7, 1883.

Application filed November 14, 18 32. (No model.)

To all whom it may concern.-

,Be it known that I, JOHN T. OBENOHAIN,

a citizen of the United States, residing at Logansport, Cass county, Indiana, have invented new and useful Improvements in Machines for indicate any irregularities on the latter by leaving on any projection on the face of the stone a touch of paint or other coloringmatter with which the red-staff is provided. These projections are then removed by means of a pick or diamond stone-dresser or other analogous devices; but it hasbeen found extremely diflicult to give a perfectly true facing to the stone in such way from the fact that it is impossible to accurately staff the stone. In using these hand devices for facing millstones, the stone has been left with a sharp, cutting, and very finely corrugated face, which to a greater or less extent abrades the bran and tears off small particles which will pass with the flour through the bolting-cloth. For these reasons it has been found difficult in the late improved mode of milling to employ millstones in gradual reduction.

It is the object of my present invention to obviate all such defects, to reduce the face of the stone, so that it shall have a smooth surface which presents only the pores or natural grit of the stone, thereby adapting it for use in gradual reduction, and to provide means whereby the fixed and running stone to be faced can both be supported and rotated in a machine adapted for the purpose, with their opposing faces in frictional contact'and' parallel with each other. In attaining this object the fixed or stationary stone of a grinding-mill is placed in a rotary carrier in the facing-machine, and the running-stone with its spindle is also placed in said machine, with its axis in a different plane from that of the stationary stone of the grinding-mill, the machine being adapted to admit of the axes of the two stones being adjusted in parallel planes, so that the faces of the stones shall be ground to a true plane, and the running-stone be ground true upon its own spindle.

In the drawings, Figure- 1 is a part section and part elevation taken on a plane indicated by dotted line 00 m, Fig. 2. Fig. 2 is a top or plan View. Fig. 3 is a detail part sectional view of one of the standards. Fig. 4 is afront elevation of the clutch." Fig. 5 is a section taken on a plane indicated by dotted line y 11 Fig. 2.

The bed or base A of this machine consists of a substantial oblong metal frame. The standards B.preferab1y cast with the bedare arranged in pairs and connected by transverse webs C, which serve to strengthen the structure.

In Figs. 1 and 2, D indicates the fixed or stationary and E the running stone of a grinding-mill, both supported in this machine in position for facing. The stone D is shown provided with a hood, F, which is permanently fitted to the stone, although in some cases-the hood is dispensed with.

G indicates a chuck which constitutes a part of this machine, and which is secured upon a horizontal shaft, H, said chuck constituting a rotary carrier for the stationary or fixed stone D of a grinding-mill. The chuck consists of a central hub, provided with a set of radial arms, 9, each carrying anangle-plate, I, which is adjustably secured upon its appropriate arm 'by means of a bolt i, passing through a longitudinal slot, 70, and having a nut which can be tightened up against the arm after the angle-plate has been properly adjusted. The lateral arms of these angle-plates are each provided with a set-screw, L, these set-screws being turned so as to clamp the stone and thereby firmly hold the same. In addition to these set-screws horizontal screws Z pass through the said angle-plates and slots, and are adapted to bear against the hood of the stone or the stone itself, so as to enable the stone to be accurately adjusted with relation to the opposite stone to be faced. v

The horizontal shaft H, which is a part of this machine, is mounted in bearings M, and is provided with a belt-pulley, m, for a driving-belt, or with any other suitable driving mechanism. The shaft N, which is shown arranged in this machine in a different plane from the plane of the shaft for the upper stone,

i 40 stone spindle at one end of the machine.

is the permanent spindle for the running-stone of a grinding-mill. This spindle is provided with a belt-pulley, N, or other driving device, and is supported in bearings M, which are in turn supported between the standards at this end of the machine. The bearings for the upper 'shaft, H, and the lower shaft or spindle, N, of the running-stone are each composed of a two-part box, as shown in Fig. 5,

and are each adjustably supported as follows:

The bearings are each maintained in position by means of set-screws O, which pass through an annular frame, 0, having a section thereof removed, so as to form a passage, 0, for the I 5 purpose of allowing the spindle to be lifted out when it is desired to remove it from the machine, or to admit of the spindle being placed in position in the apparatus. These annular frames are supported between the standards by means of set-screws P, which pass through the standards and engage the said frames. By providing one of these supporting-frames 0 between each pair of standards, the shaft H employed for rotating the 2 5'stone D can be readily placed in position in the machine or removed. The spindle of the running-stone can also be placed in position and removed with ease, and the said shaft and spindle both accurately adjusted so as to bring 0 the axes of the stones inparallel planes, and

thereby bring opposing faces of the stones parallel with each other. These millstones, when placed in the machine, rotate in vertical planes around horizontal axes which are on 3 5 different planes, power being applied so as to 4 5 turning said screw in its bearing, and thereby bring the stone E as close up to the opposite stone as may be desired. The pair of standards at this end of the machine are also each provided with a horizontal line of perfora- 5o tions, T, so that the screws which support the annular frame between such standardscan beshifted from one hole to another, according to the length of the spindle.

When the millstones are to be faced, the up- 5 5 p er stone is placed in the clutch, and the spindle carrying the lower millstone fitted in its bearings, and centered on the annular frames by means of the set-screws hereinbefore described, the said bearings being adjusted so as to bring the axes of the stones in parallel planes.

This method admits of the work being done with greater accuracy than would be possible if the running-stone were placed in the machine without its spindle. As the axis of one stoneis on a difl'erentplane from the axis of the other stone, an eccentric grinding-power is attained, and the stones quickly faced, with a minimum of power, by revolving the two holder and rotating it in contact with the stationary millstone held in a clutch device mounted on a second rotary shaft.

I make no claim for the broad idea of sharpening or facing millstones without removing them, or either of them, from the position in which they are placed for grinding by so adjusting the revolving stone with reference to the stationary one by means of screws or other suitable means that their inner or grinding surfaces shall come in contact with each other, and while in such relation causing the upper or revolving stone to rotate upon its axis, and

thus sharpen itself, as well as the stationary one. 7

What I claim is 1. In a machine for facing millstones, the

vided with a second set of bearings, arranged on a different plane from the bearings of the shaft H, forreceiving and supporting the runner-stone and its spindle and driving-pulley, substantially as and for the purpose set forth.

2. I11 a machine for facing millstones, the combination of the two sets of divided bearings M, and encircling frames 0, having openings 0,.and the frame'A, having set-screws for holding said frames with the detachable shaft H, having a clutch device for holding the sta tionary millstone supported in one set of bearings, and the runner-stone and its spindle and driving-pulley held in the otherset of bearings, substantially as and for the purpose set forth. r

In testimonywhereof Ihave hereunto set my hand in the presence of two subscribing witnesses.

JOHN T. OBENCHAIN.

Witnesses:

JAMES L. NORRIS, J. A. RUTHERFORD.

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